Hamilton, K., 1993: An examination of observed southern oscillation
effects in the northern hemisphere stratosphere. Journal of the
Atmospheric Sciences, 50(20), 3468-3473.
Abstract: The effects of the Southern Oscillation on the December-February
mean circulation in the Northern Hemisphere stratosphere were investigated
using 34 years of data. No evidence for a significant relation between
the Southern Oscillation (SO) and the zonally averaged flow is found for
any region poleward of 20°N. The effects of the tropical quasi-biennial
oscillation (QBO) on the zonal mean flow are much stronger, and this complicates
the detection of SO effects. Some more suggestive results are evident when
hemispheric maps of height anomalies at 50 or 30 mb are composited for
the warm extremes of the SO. The present findings are broadly consistent
with earlier suggestions that, on average, the Aleutian high is intensified
during the warm extremes of the Southern Oscillation. Even using the 34
years of data now available, however, the statistical significance of this
relationship cannot be demonstrated unequivocally. Once again the separation
of SO effects from QBO influences in the limited data available is a serious
problem.